The invention relates to a support device on a ski for the front part of the sole of a ski boot held by a releasable binding holding the front of the boot, including a support in which a support plate is slideably mounted transversely to the ski.
A device of this type is known from U.S. Pat. No. 6,290,251, the content of which is incorporated by reference, in the name of the applicant. In this device, the stops limiting the displacement of the support plate consist of two lateral tabs arranged diagonally on each side of the support plate and also of two projections formed on the support and which are diagonally opposed. As the tabs and the projections have to be of sufficient size in the direction of displacement of the support plate, for reasons of strength, the travel of the support plate is relatively limited. Moreover, the formation of stop tabs on the support plate has the effect of substantially reducing the width of the sides of the support plate which are engaged in the slideway formed in the support, which is detrimental to the guiding of the support plate and to its retention in the support.
An embodiment close to that referred to above is described in U.S. Pat. No. 5,921,573, the content of which is incorporated by reference.
Constructions are also known in which the return spring is a kickover spring which, at the same time, limits the displacement of the support plate. Constructions of this type are described in patent FR 2 652 508, the content of which is incorporated by reference, and in U.S. Pat. No. 5,114,174, the content of which is incorporated by reference.
U.S. Pat. No. 4,088,345, the content of which is incorporated by reference, describes a construction in which the support plate is returned elastically by a closed rubber loop. No provision is made for a stop limiting the displacement of the support plate. In the construction described in patent FR 2 125 782, the content of which is incorporated by reference, the support plate is equipped with a central stud on which the ends of two opposite wire springs bear. The stud is displaced in an aperture in the support, the ends of which form a travel-limiting stop.
A support device on a ski for the front part of the sole of a ski boot is held by a releasable binding holding the front of the boot, including a support in which a support plate is slideably mounted transversely to the ski. A limiting arrangement limits the displacement of the support plate in the support and includes stops on both the support plate and the support. A transverse helical spring is engaged partially in the support plate and partially in the support and works in compression between the support and the support plate upon displacement of the support plate.
The object of the present invention is to produce a support device using a helical return spring in which the support plate travels substantially farther than in the prior art, while being perfectly guided and held in the support.
The support device according to the invention is defined in that the stops of the support and the stops of the support plate coincide in pairs at rest in a plane perpendicular to the direction of displacement of the support plate and in that the limiting arrangement which limits the displacement of the support plate includes an auxiliary piece arranged between the stops of the support and between the stops of the support plate, free in a transverse housing formed between the support and the support plate, between the stops, the size of the auxiliary piece measured in the direction of displacement of the support plate being substantially smaller than the distance between the stops such that the auxiliary piece is entrained by the support plate until it is immobilized between one of the stops of the support and one of the stops of the support plate.
If the size of the auxiliary piece is only a fraction of the distance between the stops, the support plate travels a relatively significant distance.
The housing of the auxiliary piece is formed in the central part of the support plate such that the sides of the support plate which serve to guide and to hold the support plate in the support are not involved and can carry out their function to the full.
The auxiliary piece advantageously consists of a cylindrical stud which can move in a cylindrical housing formed half in the support and half in the support plate.
The appended drawing shows, by way of example, an embodiment of the support device according to the invention.